Improve wording and formatting of ASN.1 write module documentation

This commit is contained in:
Hanno Becker 2018-10-24 12:29:53 +01:00
parent cec1c2685f
commit 5517755353

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@ -26,139 +26,171 @@
#include "asn1.h" #include "asn1.h"
#define MBEDTLS_ASN1_CHK_ADD(g, f) do { if( ( ret = f ) < 0 ) return( ret ); else \ #define MBEDTLS_ASN1_CHK_ADD(g, f) \
g += ret; } while( 0 ) do { \
if( ( ret = f ) < 0 ) \
return( ret ); \
else \
g += ret; \
} while( 0 )
#ifdef __cplusplus #ifdef __cplusplus
extern "C" { extern "C" {
#endif #endif
/** /**
* \brief Write a length field in ASN.1 format * \brief Write a length field in ASN.1 format.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param len the length to write
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param len The length value to write.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_len( unsigned char **p, unsigned char *start, size_t len ); int mbedtls_asn1_write_len( unsigned char **p, unsigned char *start,
size_t len );
/** /**
* \brief Write a ASN.1 tag in ASN.1 format * \brief Write an ASN.1 tag in ASN.1 format.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param tag the tag to write
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param tag The tag to write.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_tag( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_tag( unsigned char **p, unsigned char *start,
unsigned char tag ); unsigned char tag );
/** /**
* \brief Write raw buffer data * \brief Write raw buffer data.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param buf data buffer to write
* \param size length of the data buffer
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param buf The data buffer to write.
* \param size The length of the data buffer.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_raw_buffer( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_raw_buffer( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t size ); const unsigned char *buf, size_t size );
#if defined(MBEDTLS_BIGNUM_C) #if defined(MBEDTLS_BIGNUM_C)
/** /**
* \brief Write a big number (MBEDTLS_ASN1_INTEGER) in ASN.1 format * \brief Write a arbitrary-precision number (#MBEDTLS_ASN1_INTEGER)
* Note: function works backwards in data buffer * in ASN.1 format.
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param X the MPI to write
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param X The MPI to write.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start, const mbedtls_mpi *X ); int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start,
const mbedtls_mpi *X );
#endif /* MBEDTLS_BIGNUM_C */ #endif /* MBEDTLS_BIGNUM_C */
/** /**
* \brief Write a NULL tag (MBEDTLS_ASN1_NULL) with zero data in ASN.1 format * \brief Write a NULL tag (#MBEDTLS_ASN1_NULL) with zero data
* Note: function works backwards in data buffer * in ASN.1 format.
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_null( unsigned char **p, unsigned char *start ); int mbedtls_asn1_write_null( unsigned char **p, unsigned char *start );
/** /**
* \brief Write an OID tag (MBEDTLS_ASN1_OID) and data in ASN.1 format * \brief Write an OID tag (#MBEDTLS_ASN1_OID) and data
* Note: function works backwards in data buffer * in ASN.1 format.
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param oid the OID to write
* \param oid_len length of the OID
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param oid The OID to write.
* \param oid_len The length of the OID.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_oid( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_oid( unsigned char **p, unsigned char *start,
const char *oid, size_t oid_len ); const char *oid, size_t oid_len );
/** /**
* \brief Write an AlgorithmIdentifier sequence in ASN.1 format * \brief Write an AlgorithmIdentifier sequence in ASN.1 format.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking) *
* \param oid the OID of the algorithm * \param p The reference to the current position pointer.
* \param oid_len length of the OID * \param start The start of the buffer, for bounds-checking.
* \param par_len length of parameters, which must be already written. * \param oid The OID of the algorithm to write.
* \param oid_len The length of the algorithm's OID.
* \param par_len The length of the parameters, which must be already written.
* If 0, NULL parameters are added * If 0, NULL parameters are added
* *
* \return the length written or a negative error code * \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_algorithm_identifier( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_algorithm_identifier( unsigned char **p,
const char *oid, size_t oid_len, unsigned char *start,
size_t par_len ); const char *oid, size_t oid_len,
size_t par_len );
/** /**
* \brief Write a boolean tag (MBEDTLS_ASN1_BOOLEAN) and value in ASN.1 format * \brief Write a boolean tag (#MBEDTLS_ASN1_BOOLEAN) and value
* Note: function works backwards in data buffer * in ASN.1 format.
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param boolean 0 or 1
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param boolean The boolean value to write, either \c 0 or \c 1.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start, int boolean ); int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start,
int boolean );
/** /**
* \brief Write an int tag (MBEDTLS_ASN1_INTEGER) and value in ASN.1 format * \brief Write an int tag (#MBEDTLS_ASN1_INTEGER) and value
* Note: function works backwards in data buffer * in ASN.1 format.
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param val the integer value
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param val The integer value to write.
*
* \return The number of bytes written to \p p on success.
* \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/ */
int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val ); int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val );
/** /**
* \brief Write a string in ASN.1 format using a specific * \brief Write a string in ASN.1 format using a specific
* string encoding tag. * string encoding tag.
* Note: function works backwards in data buffer
* \note This function works backwards in data buffer.
* *
* \param p The reference to the current position pointer. * \param p The reference to the current position pointer.
* \param start The start of the buffer (for bounds-checking). * \param start The start of the buffer, for bounds-checking.
* \param tag The string encoding tag to write, e.g. * \param tag The string encoding tag to write, e.g.
* #MBEDTLS_ASN1_UTF8_STRING. * #MBEDTLS_ASN1_UTF8_STRING.
* \param text The string to write. * \param text The string to write.
@ -169,15 +201,17 @@ int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val );
* \return A negative error code on failure. * \return A negative error code on failure.
*/ */
int mbedtls_asn1_write_tagged_string( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_tagged_string( unsigned char **p, unsigned char *start,
int tag, const char *text, size_t text_len ); int tag, const char *text,
size_t text_len );
/** /**
* \brief Write a string in ASN.1 format using the PrintableString * \brief Write a string in ASN.1 format using the PrintableString
* string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING). * string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING).
* Note: The function works backwards in data buffer. *
* \note This function works backwards in data buffer.
* *
* \param p The reference to the current position pointer. * \param p The reference to the current position pointer.
* \param start The start of the buffer (for bounds-checking). * \param start The start of the buffer, for bounds-checking.
* \param text The string to write. * \param text The string to write.
* \param text_len The length of \p text in bytes (which might * \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters). * be strictly larger than the number of characters).
@ -192,10 +226,11 @@ int mbedtls_asn1_write_printable_string( unsigned char **p,
/** /**
* \brief Write a UTF8 string in ASN.1 format using the UTF8String * \brief Write a UTF8 string in ASN.1 format using the UTF8String
* string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING). * string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING).
* Note: The function works backwards in data buffer. *
* \note This function works backwards in data buffer.
* *
* \param p The reference to the current position pointer. * \param p The reference to the current position pointer.
* \param start The start of the buffer (for bounds-checking). * \param start The start of the buffer, for bounds-checking.
* \param text The string to write. * \param text The string to write.
* \param text_len The length of \p text in bytes (which might * \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters). * be strictly larger than the number of characters).
@ -207,12 +242,13 @@ int mbedtls_asn1_write_utf8_string( unsigned char **p, unsigned char *start,
const char *text, size_t text_len ); const char *text, size_t text_len );
/** /**
* \brief Write a string in ASN.1 format using the IA5tring * \brief Write a string in ASN.1 format using the IA5String
* string encoding tag (#MBEDTLS_ASN1_IA5_STRING). * string encoding tag (#MBEDTLS_ASN1_IA5_STRING).
* Note: The function works backwards in data buffer. *
* \note This function works backwards in data buffer.
* *
* \param p The reference to the current position pointer. * \param p The reference to the current position pointer.
* \param start The start of the buffer (for bounds-checking). * \param start The start of the buffer, for bounds-checking.
* \param text The string to write. * \param text The string to write.
* \param text_len The length of \p text in bytes (which might * \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters). * be strictly larger than the number of characters).
@ -224,34 +260,38 @@ int mbedtls_asn1_write_ia5_string( unsigned char **p, unsigned char *start,
const char *text, size_t text_len ); const char *text, size_t text_len );
/** /**
* \brief Write a bitstring tag (MBEDTLS_ASN1_BIT_STRING) and * \brief Write a bitstring tag (#MBEDTLS_ASN1_BIT_STRING) and
* value in ASN.1 format * value in ASN.1 format.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param buf the bitstring
* \param bits the total number of bits in the bitstring
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param buf The bitstring to write.
* \param bits The total number of bits in the bitstring.
*
* \return The number of bytes written to \p p on success.
* \return A negative error code on failure.
*/ */
int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t bits ); const unsigned char *buf, size_t bits );
/** /**
* \brief Write an octet string tag (MBEDTLS_ASN1_OCTET_STRING) and * \brief Write an octet string tag (#MBEDTLS_ASN1_OCTET_STRING)
* value in ASN.1 format * and value in ASN.1 format.
* Note: function works backwards in data buffer
* *
* \param p reference to current position pointer * \note This function works backwards in data buffer.
* \param start start of the buffer (for bounds-checking)
* \param buf data buffer to write
* \param size length of the data buffer
* *
* \return the length written or a negative error code * \param p The reference to the current position pointer.
* \param start The start of the buffer, for bounds-checking.
* \param buf The buffer holding the data to write.
* \param size The length of the data buffer \p buf.
*
* \return The number of bytes written to \p p on success.
* \return A negative error code on failure.
*/ */
int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start, int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t size ); const unsigned char *buf, size_t size );
/** /**
* \brief Create or find a specific named_data entry for writing in a * \brief Create or find a specific named_data entry for writing in a
@ -259,15 +299,16 @@ int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start,
* a new entry is added to the head of the list. * a new entry is added to the head of the list.
* Warning: Destructive behaviour for the val data! * Warning: Destructive behaviour for the val data!
* *
* \param list Pointer to the location of the head of the list to seek * \param list The pointer to the location of the head of the list to seek
* through (will be updated in case of a new entry) * through (will be updated in case of a new entry).
* \param oid The OID to look for * \param oid The OID to look for.
* \param oid_len Size of the OID * \param oid_len The size of the OID.
* \param val Data to store (can be NULL if you want to fill it by hand) * \param val The data to store (can be \c NULL if you want to fill
* \param val_len Minimum length of the data buffer needed * it by hand).
* \param val_len The minimum length of the data buffer needed.
* *
* \return NULL if if there was a memory allocation error, or a pointer * \return A pointer to the new / existing entry on success.
* to the new / existing entry. * \return \c NULL if if there was a memory allocation error.
*/ */
mbedtls_asn1_named_data *mbedtls_asn1_store_named_data( mbedtls_asn1_named_data **list, mbedtls_asn1_named_data *mbedtls_asn1_store_named_data( mbedtls_asn1_named_data **list,
const char *oid, size_t oid_len, const char *oid, size_t oid_len,